Piano-vibraphone



April 1943- G. A. Q'CONNELL EIAL 2,315,812

PIANO-VIBRAPHONE Filed April 7, 1941 3 Sheets-Sheet l April 1943- G. A.O'CONNELL EIIIAIL ,812

PIANO-VIBRAPHONE 3 Shets-Sheet 2 Filed April 7, 1941 P G. A O'CONNELLETAL 2,315,812

PIANO-VIBRAPHONE Filed April 7, 1941 5 Sheets-Sheet 3 Patented Apr; 6,1943 UNITED STATES PATENT OFFICE PIANO -VIBRAPHONE Gerald A. OConnelland Carl M. Larson, De Kalb, Ill.

9 Claims.

This invention relates to a new and improved musical instrument known asa piano-vibraphone in which the notes are sounded not by hammers held inthe hands of the player but by means of a piano type action having theusual keys adapted to be depressed by the fingers.

The principal object of our invention is to provide a piano-Vibraphoneor piano-Xylophone in which all of the bells or bars adapted to besounded by striking contact therewith of the hammers of the piano actionhave individual dampers separately actuated in timed relation with therelated hammers, and also adapted to be worked as a group by means ofpedals, thus providing an instrument having desirable playing qualitiesand capable of rendering otherwise difficult musical compositions withcomparative ease, and making such Xylophone or Vibraphone music possibleat the hands of relatively unskilled players. The music obtained withthis instrument is moreover of a superior quality to what is obtainedwith the conventional Xylophone or Vibraphone even with an expertxylophonist, inasmuch as the present instrument makes available the sameloud and soft pedal effects as in an ordinary piano, whereas on theconventional Xylophone or Vibraphone the player was necessarily limitedin the musical eliects he could obtain, inasmuch as the dampers werearranged to be all on or off, under the control of a foot pedal.

A salient feature of the present instrument is the utilization of anupright piano type action modified only to the extent necessary to adaptit to having the hammers strike the vertically hung bars of theXylophone part of the instrument, whereby to obtain the desired ease andspeed of playing, sensitivity, good response to loud and soft playing,and quick and effective damping obtainable in such piano actions, all ofwhich taken with the vertical positioning of the bars makes for aninstrument of higher standard than might be expected or has beenproduced in the past where Xylophone bars have been arranged to besounded from a keyboard.

Another important object of our invention is to provide an instrument ofthe kind mentioned which can be housed within a comparatively small andcompact case for easy transportation, and so as to take up minimum spacein an orchestra pit or any playing platform and wherever the compactnessmay be of particular advantage. The instrument is moreover provided witha hinged extensible keybed which when not extended in playing positionis adapted to be swung upwardly and inwardly with respect to the case toan out of the way position, so that the instru ment then takes up evenless space than before, the foldable keybed in folded position enablingeasier passage through narrow doorways and hallways through which it mayoften be desired to move the instrument. The keybed, in accordance withour invention, is preferably equipped with a pair of props for rigidsupport thereof in playing position, the props when not in use beingfoldable inwardly to an out of the way position in the base portion ofthe case.

Another important object of our invention is to provide an instrument ofthe kind mentioned in which the Vibraphone or Xylophone section ismounted on a sounding board forming the back of the case, just enoughspace being left between the frame of the Vibraphone and the soundingboard for the resonating tubes, the longer ones of which are bentatright angles for compactness. The supporting frame of the piano actionattaches to the frame of the Vibraphone so as to dispose the hammers infront of the bars between the side walls of the case. The front of thecase is for the most part left open except for a fabric shield above andbelow the keybed, thus allowing the sound to be thrown forwardly withminimum obstruction.

Another object consists in the provision of a drop action below theelevation of the keybed, all of the hammers of the piano action havingstickers extending upwardly from the action for connection with the armsof intermediate cross-rods, and all of the keys of the keybed havingstickers extending downwardly therefrom forconnection with other arms onsaid intermediate cross-rods, whereby keys of conventional width forthree octaves on a short length keyboard are enabled to sound the notesof a much longer conventional full length Vibraphone, although ourinvention contemplates the shifting of the bars closer together so as topermit shortening the case and shortening the connections between thekeys and hammers.

These and other objects of our invention will be brought out more fullyin the course of the following detailed description, in which referenceis made to the accompanying drawings, wherein- Figure 1 is a perspectiveview of a pianovibraphone made in accordance with our invention, thesame being shown on a small scale;

Fig. 2 is a view partly in vertical section and partly in end elevationof the instrument shown in Fig. l, but on a larger scale;

Fig. 3 is a top plan view of the instrument on a slightly smaller scalethan it appears in Fig. 2 and with the top and fabric front coveringremoved to better disclose the Vibraphone and piano action;

Fig. 4 is a front elevational view of Fig. 3, with the intermediatecross-rods on the left or bass end of the instrument broken away betterto reveal the piano action and Vibraphone therebehind;

Fig. is an enlarged front view of a portion of the intermediatecross-rods and their mountings, these being the cross-rods broken awayin Fig. 4, and

Fig. 6 is an enlarged vertical sectional detail showing the relationshipof the hammers of the piano action to the bells and the operatingconnections between the hammers and the keys.

The same reference numerals are applied tocorresponding parts throughoutthe views.

The reference numeral 1 designates the base portion of the case 8 forthe piano-Vibraphone, which is suitably equipped with casters 9 forroller support. I!) is the sounding board on the back frame II of thecase, and i2 and I3 are side panels, and M a hinged top panel. Thus thefront of the case is left open for unobstructed transmission of soundforwardly from the case, there being only a fabric shield I5 reachingfrom top to bottom to conceal the mechanism in the case with minimumobstruction to the passage of sound through the open front of the case.A keybed l6 pivoted at I1 on brackets I 8 rising from a frontcross-member l9 in the case is supported partly by the cross-member andpartly by a pair of props 20 when unfolded to playing position. There isa cut-out portion 2! in the top panel which accommodates the keybed inits folded out of the way position. A ledge 22 below the cut-out portion2| of the top 14 and approximately level with the upper portion of thekeybed provides a convenient support for the music book or sheet music,and we also contemplate providing fluorescent light bulbs 23 forillumination of the music in side panels 24 adjacent the ledge 22,arranged to be turned on or off by means of a switch 25 at a convenientpoint on the front of the case. The props 20 are pivoted at their lowerends on the base portion 7, as indicated at 25, and have their upperends tapered, as indicated at 21, to fit in sockets 28 provided thereforin the bottom of the keybed. When not in use the props are arranged tobe folded downwardly onto the base portion so as to be out of the way,as indicated in dotted lines in Fig. 1. With the props folded in thatmanner and the keybed also folded out of the way, it is apparent thatthe instrument is reduced to a very small dimension front to back andcan, therefore, be easily moved through narrow doorways and hallways asis so frequently necessary in the use of an instrument of this kind.Furthermore when not in use the instrument will not take up much spacein an orchestra pit or on a playing platform. The compactness also is ofconsiderable advantage in the transportation of the instrument fromplace to place. In passing it will be noted that the top panel H in theplaying of the instrument may, if desired, be raised, as indicated indotted lines in Fig. 2, and sup-ported in such position by means of oneor more props 2 9 cooperating with keepers 30 on the side panels I2 andI3.

The case 8 contains a Vibraphone, indicated generally by the referencenumeral 3|, the bars or bells 32 of which are arranged to be struck bythe felt hammers 33 of a piano action, indicated generally by thereference numeral 34. The latter is operable by stickers 35, each ofwhich extends upwardly from the lower portion of the piano action and isattached to an arm 36 on the outer end of an intermediate cross-rod 31.There is related to each of the stickers another sticker 38 attached toan arm 39 on the inner end of the related cross-rod 31. These stickers38 extend upwardly and are attached to levers 40 pivotally mounted onthe inner ends of the keys 4!. The keys 4| are fulcrumed intermediatetheir ends in the usual way on a pivot rail 42 by means of vertical pins:13 projecting upwardly from the rail into upwardly flaring holes in thekeys. Capstan screws 44, threaded in holes in the levers 40, bear onfelt pads on the inner ends of the keys and are arranged to be adjustedso as to take up all slack in the connections between the keys 4| andthe piano action 34, so that there is substantially no lost motion andthe instant a key M is depressed its related hammer 33 is actuated. Thepivotal connections 4.6 between the levers 40 and stickers 38 are inapproximate alignment with the hinging axis I! of the keybed l 6, sothat the keybed is free to fold upwardly or downwardly without anyappreciable movement of the keys M or hammers 33. The fact that thelevers 40 are pivoted on the keys at 41 is of advantage in the foldingof the keybed, because the levers are therefore free to swing outwardlyaway from the inner end of the keys when the keybed is folded, and inthat way the piano action parts are not kept under any unusual tensionduring the time that the keybed is folded. A cross-bar 42a on the keybedextends over the fulcrumed portions of the keys and, serves to maintainthe same in proper relation to the pivot rail 42 and pivot pins 43 whenthe. keybed is folded. This cross-bar as well as that portion of thekeys behind. the same is suitably concealed under a cover Ilia over theinner portion of the keybed, leaving only the usual length of each keyexposed for playing purposes. The cross-rods. 3'! are supported for freeoscilla tion in tubular bearings 48 mounted in hangers 49 reachingdownwardly from the cross-member [9. The upward pull on any one of thestickers 38 incident to the depression of a certain key 41 istransmitted through the related cross-rod 31 by means of the arms 35 and39 at the opposite ends of the cross-rod to the related sticker 35, soas to actuate the related hammer 33. The cross-rods 3'! are of varyinglengths, shortest for the middle keys and longest for the end keys, sothat a standard width of piano key can be used and operating connectionsestablished between all of the keys in the three octave keyboard and thehammers 33 for sounding the bells or bars 32 of the three octaveVibraphone 3%. There is an appreciable difference in length between thekeyboard and the Vibraphone, a standard length vibraphone being hereinshown, having the sharps in the customary dispersed relationship. Inactual practice, however, all of the bars may be brought closer togetherto permit proportionate shortening of the case and shortening of theconnections between the keys and hammers, there being no necessity in aninstrument of the present type, as there is in the ordinary Xylophone orVibraphone, for arranging the bells or bars in a special way forconvenience in striking the same with hammers held in the hands. Inother words, it is immaterial in an instrument of the present typewhether the sharps are in one row and the naturals in another so long asa given key 4! for a designated note will sound that note through itsconnections with the proper hammer. The bells or bars 32, in otherwords, may be arranged in uniformly or non-uniformly spaced relation intwo rows, both for greatest compactness and for most convenientcooperation with the hammers of the piano action, although in thepresent disclosure the piano action has been constructed to adapt it tothe conventional Xylophone or Vibraphone.

The Vibraphone 3| has the opposite ends of the frame 50 mounted on thesounding board 10, as indicated at 5|, so that the bars 32 carried onthe frame on spring tensioned cords 52 in the usual way are disposed ina substantially vertical plane parallel to the sounding board. Enoughspace is left between the frame 50 and sounding board ID for theresonating tubes 53 associated with the bars, the longer ones of thesetubes being bent to elbow form, as indicated at 54, so that the case canbe kept down to the small front to back dimensions shown. than has beenindicated in the drawings is actually possible, it being apparent inFig. 2 that the space between the frame 50 and sounding board Ill couldeasily be reduced still further if the el bow-shaped tubes 53 wereformed with longer vertical portions 54 and proportionately shorterhorizontal portions. We have found that the vertical positioning of thebars 32 does not affect the tone quality of the Vibraphone, and it iswell known that whereas the conventional Xylophones and vibraphones havestraight resonator tubes, the tone quality is not affected by havingthese tubes of elbow form so long as the length of the air columns isnot changed. Each of the tubes has a butterfly valve 55 and all of thesevalves in each row of bars are on a common shaft 56 arranged to bedriven by an electric motor 51 through belt and pulley connectionsindicated at 58. These Valves serve to produce a pulsating or vibratoeiiect and, depending upon the musical selection being played, will betiuned at a higher or lower speed by varying the speed of the motor 51.The motor speed control button is indicated at 59 on the front of thecase and has a flexible shaft connection (not shown) with the motorspeed regulator (not shown). At 58 (Fig. l) is indicated the switch. onthe front of the case for starting and stopping the motor 51. While wehave disclosed a Vibraphone equipped with the butterfly valves 55, itshould be understood that we do not limit our invention to the use ofthese valves, inasmuch as the individual dampers provided in accordancewith our invention. for all of the bars serve much more effectively toprevent undesired mingling of musical tones of like or different pitch.

A drop type piano action is disclosed at 34, the keyboard being atapproximately conventional piano elevation above the action. The actionis approximately in the same horizontal plane with the lower row of bars32, with the hammers 33, in the plane of the upper end portions of thelower row of bars and the lower portion of the upper row of bars, asclearly appears in Figs. 2 and 6. The action is supported on bracket Bl,which are secured to the frame 50 of the vibraphone for support and arealso supported on a cross-member 62 in the case. The main rail 63 of theaction is rigidly supported on the brackets, and the same is true of thespring rail 64. The hammer rail 65 is pivotally mounted on the brackets61, as indicated at 66. The damper rail Greater compactness bars.

in contact therewith under tension of the springs 68. However when thesoft pedal 10 is depressed, the lever H fulcrumed on the spring 12causes the push-rod 13 to swing the hammer rail Y inwardly toward thehammers and thus shorten the are of their possible travel andaccordingly soften the blows they can deliver on the bars. It isunderstood, of course, that the hammers 33 are all pivoted on the mainrail 63, as at 14, the shorter armed hammers being provided to strikethe upper end portions of the lower row of bars 32 and longer armedhammers being provided to strike the lower end portions of the upper rowof bars 32. The hammers have their butts 15 operatively engaged by jacks16, which, in turn, are operated by lever ll connected with the stickers35, the levers 11 being pivoted, as at 18, on the main rail 63. At I9are indicated the usual back checks, and at the usual let-off buttons.Fingers 8| pivoted as at 82 on the main rail carry dampers 83, one foreach of the bars 32. Springs 84 normally urge the dampers intoengagement with the bars 32, but each lever 71 carries a spoon 85cooperating with the lower end of the adjacent finger 8| to release thedamper on a given bar When that bar is struck by its related hammer 33.In the return of the hammer the spoon 85 is retracted and the damper isreplaced under action of its spring 84, unless the player depressed theloud pedal 86, in which event the lever 81, is tilted on its fulcrumspring 88 and the push-rod 89 connected to the damper rail 61 swings thelatter inwardly against the lower end portions of the fingers 8 I, thusholding all of the dampers 83 away from the bars 32. The pedal 86 isdepressed only when it is desired to have tones intermingled. Otherwisethe dampers 83, with or without the butterfly valves 55, serveeffectively to prevent undesired mingling of tones and the quality ofmusic obtainable is accordingly greatly improved beyond that obtainablein the ordinary Xylophone or Vibraphone, where individual damper actionis not obtainable, the rotary butterfly valves being only partiallyeffective in that direction. The dampers 83 for the upper row of bars 32are disposed high enough on those bars so that the longer armed hammers33 can strike below the same, the slender wire arms 90 leavingsufficient room alongside the same for the hammers to reach the So faras the dampers 83 for the lower row of bars are concerned, they are alldisposed in laterally offset relation to the center lines of those bars,as clearly appears in Fig. 4, so that the shorter armed hammers 33cooperating with those bars have room enough to strike the bars on theopposite side of the longitudinal center lines with respect to thedampers.

In operation, the present instrument enables a pianist of average skillto play musical compositions which would be far too difiicult for theaverage xylophonist to play with hammers, and the quality of musicobtainable with the present instrument is greatly improved over what isobtainable with the ordinary Xylophone or vibraphone, due to the factthat there is no undesired intermingling of tones and the instrument hassuch flexibility of expression with the soft and loud pedals I3 and 86respectively. The ordinary Xylophone, on the other hand, has no way ofavoiding undesired intermingling of tones, while the ordinary Vibraphoneonly partially avoids such mingling by the provision of the rotatingbutterfly valves. In both of these last-named instruments, however, thedamper is on or off for all of the bars and there are not individualdampers, and accordingly the power of musical expression is limited, thequality of the music obtainable is lowered, and the entire rang of theinstruments, so far as the kinds of music for which they are suitable isconcerned, is greatly reduced. Those objections are eliminated in thepresent instrument and for that reason the present instrument isconsidered suitable for many occasions and types of entertainment wherethe others would be unsuitable. In conclusion, it is also consideredsafe to assume that any novice can in a given time become fairlyproficient in th playing of the present instrument, whereas he wouldfind it required a much longer time to become as proficient in theplaying of an ordinary Xylophone or Vibraphone.

It is believed the foregoing description conveys a good understanding ofthe objects and advantages of our invention. The appended claims havebeen drawn to cover all legitimate mod fications and adaptations.

We claim:

1. A musical instrument of the Xylophone type, including twosubstantially parallel rows of vertically hung bars, one row beingspaced above the other, each of said bars being adapted when struck tobe set into vibration to produce a tone of a musical scale differingfrom the tones produced by the others, an individual hammer for strikingeach of said bars, all of the hammers being pivoted on a common supportextending in spaced parallel relation to one of said rows of bars, allof the hammers extending from said support in the same direction, thehammers for striking the bars of the adjacent row being of one radiusand the hammers for striking the bars of the other row being of anotherradius, finger operable key means for operating the hammers, anindividual damper for each of said bars normally spring pressed intoengagement therewith, means associated with each hammer to move therelated damper out of engagement with the bar when the hammer isactuated to strike the bar, all of said dampers being pivoted on theaforesaid hammer support and extending all in one direction from saidsupport, the dampers for engaging the bars of the adjacent row being ofone radius and the dampers for engaging the bars of the other row beingof another radius, the dampers for engagement with the bars of the rowadjacent said support having engagement with said bars in laterallyoffset relation to the longitudinal center lines of said bars, and therelated hammers being mounted on said support so as to strike said barson the opposite side of the longitudinal center lines, and means formoving all of said dampers out of engagement with all of said barsindependently of the operation of said hammers.

2. A musical instrument of the Xylophone type, including a row ofvertically hung bars, each adapted when struck to be set into vibrationto produce a tone of a musical scale differing from the tones producedby the others, an individual hammer for striking each of said bars,finger operable key means for operating the hammers, an individualresonator tube for each of said bars, individual valve means for openingand closing each of said tubes, power operated means for operating allof said valvemeans to open and close all of said tubes in unison, anindividual damper for each of said bars normally spring pressed intoengagement therewith, means associated with each hammer to move therelated damper out of engagement with the bar when the hammer isactuated to strike the bar, and means for moving all of said dampers outof engagement with all of said 'bars independently of the operation ofsaid hammers.

3. A musical instrument of the Xylophone type, including a row ofvertically hung bars, each adapted when struck to be set into vibrationto produce a tone of a musical scale differing from the tones producedby the others, an individual hammer for striking each of said bars,finger operable key means for operating the hammers, individual springmeans normally urging the hammers away from the bars, means for movingall of said hammers in the opposite direction independently of said keymeans against the action of said springs, an individual resonator tubefor each of said bars, individual valve means for opening and closingeach of said tubes, power operated means for operating all of said valvemeans to open and close all of said tubes in unison, an individualdamper for each of said bars normally spring pressed into engagementtherewith, means associated with each hammer to move the related damperout of engagement with the bar when the hammer is actuated to strike thebar, and means for moving all of said dampers out of engagement with allof said bars independently of the operation of said hammers.

4. A Xylophone type musical instrument, comprising a substantiallyvertical sounding board, a frame carried on the sounding board in spacedsubstantially parallel relation thereto, a row of vibrant bars supportedin a substantially vertical plane on said irame, each of said barsadapted when set into vibration to produce a tone of a musical scalediffering from the tones produced by the others, and an individualtubular resonator for each of said bars extending from the frame towardthe sounding board, the longer ones of said resonators being of greaterlength than the distance from the frame to the sounding board and beingof elbow form, with the excess end length extending in closely spacedsubstantially parallel relation to the sounding board.

5. A Xylophone type musical instrument, comprising a substantiallyvertical sounding board, a frame carried on the sounding board in spacedsubstantially parallel relation thereto, a row of vibrant bars supportedin a substantially vertical plane on said frame, each of said barsadapted when set into vibration to produce a tone of a musical scalediffering from the tones produced by the others, an individual tubularresonator for each of said bars extending from the frame toward thesounding board, a. case for said instrument including said soundingboard in upright position as the back wall thereof, said case alsoincluding bottom, side, and top walls, a piano action mounted in saidcase between the side walls thereof, including hammers arranged whenactuated to strike the bars and also including an individual damper for.each of said bars normally engaging the bars but arranged to bereleased in timed relation with the operation of said hammers, a keybedmounted on the front of said case and a keyboard thereon including anindividual key operatively connected with each of the hammers andrelated dampers.

6. A xylophone type musical instrument, comprising a sounding board, arow of vibrant bars supported on a frame carried on the sounding boardin spaced substantially parallel relation thereto, each of said barsadapted when set into vibration to produce a tone of a musical scalediffering from the tones produced by the others, an individual tubularresonator for each of said bars extending from the frame toward thesounding board, a case for said instrument including said sounding boardin upright position as the back wall thereof, said case also includingbottom, side, and top Walls, a piano action mounted in said case betweenthe side walls thereof, including hammers arranged when actuated tostrike the bars and also including an individual damper for each of saidbars normally engaging the bars but arranged to be released in timedrelation with the operation of said hammers, a keybed mounted on thefront of said case and a keyboard thereon including an individual keyoperatively connected with each of the hammers and related dampers, andfabric shield means for the front of the case, substantially from top tobottom, serving to conceal the mechanism within the case withoutappreciably interfering with the outlet of sound from the case forwardlyfrom the sounding board.

7. A xylophone type musical instrument, comprising a sounding board, arow of vibrant bars supported on a frame carried on the sounding boardin spaced substantially parallel relation thereto, each of said barsadapted when set into vibration to produce a tone of a musical scalediffering from the tones produced by the others, an individual tubularresonator for each of said bars extending from the frame to ward thesounding board, a case for said instrument including said sounding boardin upright position as the back wall thereof, said case also includingbottom, side, and top walls, a piano action mounted in said case betweenthe side Walls thereof, including hammers arranged when actuated tostrike the bars and also including an individual damper for each of saidbars normally engaging the bars but arranged to be released in timedrelation with the operation of said hammers, a keybed mounted on thefront of said case and a keyboard thereon including an individual keyoperatively connected with each of the hammers and related dampers, thekeybed in its operative position projecting forwardly from the case andbeing pivoted relative to the case on a substantially horizontal axisfor swinging movement upwardly and inwardly relative to the case to aninoperative out of the. way position, the keys of the keyboard havingtheir operating connections with the hammers of the piano action,including pivotal connections, substantially coincident with the pivotalaxis of said keybed.

8. A xylophone type musical instrument, comprising a sounding board, a.row of vibrant bars supported on a frame carried on the sounding boardin spaced substantially parallel relation thereto, each of saidbarsadapted when set into vibration to produce a tone of a musical scalediifering from the tones produced by the others, an individual tubularresonator for each of said bars extending from the frame toward thesounding board, a case for said instrument including said sounding boardin upright position as the back wall thereof, said case also includingbottom, side, and top walls, a piano action mounted in said case betweenthe side walls thereof, including hammers arranged when actuated tostrike the bars and also including an individual damper for each of saidbars normally engaging the bars but arranged to be released in timedrelation with the operation of said hammers, a keybed mounted on thefront of said case and a keyboard thereon including an individual keyoperatively connected with each of the hammers and related dampers, thekeybed in its operative position projecting forwardly from the case andbeing pivoted relative to the case on a substantially horizontal axisfor swinging movement upwardly and inwardly relative to the case to aninoperative out of the way position, the keys of the keyboard havingtheir operating connections with the hammers of the piano action,including pivotal connections, substantially coincident with the pivotalaxis of said keybed, and prop means detachably connectable with thekeybed and extending upwardly from the case to the keybed for rigidsupport of the latter in the unfolded operative position.

9. A musical instrument of the xylophone type, including twosubstantially parallel rows of vertically hung bars, one row beingspaced above the other, each of said bars being adapted when struck tobe set into vibration to produce a tone of a musical scale differingfrom the tones produced by the others, an individual hammer for strikingeach of said bars, all of the hammers being pivoted on a common supportextending in spaced parallel relation to one of said rows of bars, allof the hammers extending from said support in the same direction, thehammers for striking the bars of the adjacent row being of one radiusand the hammers for striking the bars of the other row being of anotherradius, finger operable key means for operating the hammers, anindividual damper for each of said bars normally spring pressed intoengagement therewith, means asso ciated with each hammer to move therelated damper out of engagement with the bar when the hammer isactuated to strike the bar, all of said dampers being pivoted on theaforesaid hammer support and extending all in one direction from saidsupport, the dampers for engaging the bars of the adjacent row being ofone radius and the dampers for engaging the bars of the other row beingof another radius, and means for moving all of said dampers out ofengagement with all of said bars independentlyof the operation of saidhammers.

GERALD A. OCONNELL. CARL M. LARSON.

